Like this:

The Rackspace open cloud is built on the open-source OpenStack framework, founded by Rackspace and NASA in July 2010. You can now host your cloud in your data centre, at Rackspace, or with a third party. We can support your private cloud, or you can choose to manage it yourself. Tools. SDKs, language bindings, API documentation and Rackspace projects on Github provide tools for languages like Java, Python, PHP and C#.